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Topic Review

Google Home is a line of smart speakers developed by Google under the Google Nest brand. The devices enable users to speak voice commands to interact with services through Google Assistant, the company's virtual assistant. Both in-house and third-party services are integrated, allowing users to listen to music, control playback of videos or photos, or receive news updates entirely by voice. Google Nest devices also have integrated support for home automation, letting users control smart home appliances with their voice command. The first device, Google Home, was released in the United States in November 2016; subsequent product releases occurred globally from 2017–2019. Through software updates to Google Nest devices and Google Assistant, additional functionality has been added over time. For example, multiple speakers can be set up for synchronized playback of music. An update in April 2017 brought multi-user support, allowing the device to distinguish between up to six people by voice. In May 2017, Google announced multiple updates, including: hands-free phone calling at no cost in Canada and the United States; proactive reminders ahead of scheduled events; visual responses on mobile devices or Chromecast-enabled televisions; Bluetooth audio streaming; and the ability to add reminders and calendar appointments. The original Google Home speaker released in November 2016 featured a cylindrical shape with colored status LEDs on top. In October 2017, Google announced two additions to the product lineup, the miniature puck-shaped Google Home Mini and a larger Google Home Max. In October 2018, the company released the Google Home Hub, a smart speaker with a 7-inch touchscreen. In May 2019, Google announced that Google Home devices would be rebranded under the Google Nest banner and unveiled a larger smart display called the Google Nest Hub Max.

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09 Nov 2022

Topic Review

A paternoster (/ˈpeɪtərˈnɒstər/, /ˈpɑː-/, or /ˈpæ-/) or paternoster lift is a passenger elevator which consists of a chain of open compartments (each usually designed for two persons) that move slowly in a loop up and down inside a building without stopping. Passengers can step on or off at any floor they like. The same technique is also used for filing cabinets to store large amounts of (paper) documents or for small spare parts. The much smaller belt manlift which consists of an endless belt with steps and rungs but no compartments is also sometimes called a paternoster. The name paternoster ("Our Father", the first two words of the Lord's Prayer in Latin) was originally applied to the device because the elevator is in the form of a loop and is thus similar to rosary beads used as an aid in reciting prayers. The construction of new paternosters was stopped in the mid-1970s due to safety concerns, but public sentiment has kept many of the remaining examples open. By far most remaining paternosters are in Europe, with 230 examples in Germany, and 68 in the Czech Republic. Only three have been identified outside Europe: one in Malaysia, one in Sri Lanka, and another in Peru.

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01 Nov 2022

Topic Review

Starlink (Satellite Constellation)

Starlink is a satellite constellation being constructed by American company SpaceX to provide satellite Internet access. The constellation will consist of thousands of mass-produced small satellites, working in combination with ground transceivers. SpaceX also plans to sell some of the satellites for military, scientific or exploratory purposes. (As of January 2020), SpaceX has deployed 182 satellites. They plan to deploy 60 more per Falcon 9 launch, with launches as often as every two weeks after late 2019. In total, nearly 12,000 satellites will be deployed by the mid-2020s, with a possible later extension to 42,000. The initial 12,000 satellites are planned to orbit in three orbital shells: first placing approximately 1,600 in a 550-kilometer-altitude (340 mi) shell, then approximately 2,800 Ku- and Ka-band spectrum satellites at 1,150 km (710 mi) and approximately 7,500 V-band satellites at 340 km (210 mi). Commercial operation could begin in 2020. Concerns have been raised about the long-term danger of space junk resulting from placing thousands of satellites in orbits above 1,000 kilometres (620 mi) and a possible impact on astronomy, although SpaceX is reportedly attempting to solve the issue. The total cost of the decade-long project to design, build and deploy the constellation was estimated by SpaceX in May 2018 to be about US$10 billion. Product development began in 2015, with the first two prototype test-flight satellites launched in February 2018. A second set of test satellites and the first large deployment of a piece of the constellation occurred on 24 May 2019 (UTC) when the first 60 operational satellites were launched. The SpaceX satellite development facility in Redmond, Washington, houses the Starlink research, development, manufacturing and on-orbit control operations.

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11 Nov 2022

Topic Review

Armor-Piercing Ammunition

Armour-piercing ammunition (AP) is a type of projectile designed to penetrate either body armour or vehicle armour. From the 1860s to 1950s, a major application of armour-piercing projectiles was to defeat the thick armour carried on many warships and cause damage to their lightly-armoured interiors. From the 1920s onwards, armour-piercing weapons were required for anti-tank missions. AP rounds smaller than 20 mm are intended for lightly-armoured targets such as body armour, bulletproof glass and lightly-armoured vehicles. As tank armour improved during World War II, anti-vehicle rounds began to use a smaller but dense penetrating body within a larger shell, firing at very high muzzle velocity. Modern penetrators are long rods of dense material like tungsten or depleted uranium (DU) that further improves the terminal ballistics.

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12 Oct 2022

Topic Review

A hybrid regime is a mixed type of political regime that is often created as a result of an incomplete transition from an authoritarian regime to a democratic one. Hybrid regimes combine autocratic features with democratic ones and can simultaneously hold political repressions and regular elections. The term hybrid regime arises from a polymorphic view of political regimes that opposes the dichotomy of autocracy or democracy. Hybrid regimes are characteristic of resource countries such as petro-states. Those regimes are stable and tenacious. Western researchers analyzing hybrid regimes pay attention to the decorative nature of democratic institutions (elections do not lead to a change of power, different media broadcast government point of view and the opposition in parliament votes the same way as the ruling party, among others), from which it is concluded that authoritarianism is the basis of hybrid regimes. However, hybrid regimes also imitate dictatorship while having a relatively lower level of violence.

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18 Nov 2022

Topic Review

Cholera Outbreaks and Pandemics

Seven cholera pandemics have occurred in the past 200 years, with the first pandemic originating in India in 1817. Additionally, there have been many documented cholera outbreaks, such as a 1991–1994 outbreak in South America and, more recently, the 2016–2021 Yemen cholera outbreak. Although much is known about the mechanisms behind the spread of cholera, this has not led to a full understanding of what makes cholera outbreaks happen in some places and not others. Lack of treatment of human feces and lack of treatment of drinking water greatly facilitate its spread. Bodies of water have been found to serve as a reservoir, and seafood shipped long distances can spread the disease. Between 1816 and 1923, the first six cholera pandemics occurred consecutively and continuously over time. Increased commerce, migration, and pilgrimage are credited for its transmission. Late in this period (particularly 1879–1883), major scientific breakthroughs toward the treatment of cholera develop: the first immunization by Pasteur, the development of the first cholera vaccine, and identification of the bacterium Vibrio cholerae by Filippo Pacini and Robert Koch. After a long hiatus, a seventh cholera pandemic spread in 1961. The pandemic subsided in the 1970s, but continued on a smaller scale. Outbreaks occur across the developing world to the current day. Epidemics occurred after wars, civil unrest, or natural disasters, when water and food supplies had become contaminated with Vibrio cholerae, and also due to crowded living conditions and poor sanitation. Deaths in India between 1817 and 1860 in the first three pandemics of the nineteenth century, are estimated to have exceeded 15 million people. Another 23 million died between 1865 and 1917, during the next three pandemics. Cholera deaths in the Russian Empire during a similar time period exceeded 2 million.

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20 Oct 2022

Topic Review

Ohaguro (お歯黒) is a custom of dyeing one's teeth black. It was most popular in Japan until the Meiji era. Tooth painting is also known and practiced in the southeastern parts of China , Pacific Islands and Southeast Asia. Dyeing is mainly done by married women, though occasionally men do it as well. It was also beneficial, as it prevented tooth decay, in a similar fashion to modern dental sealants.

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19 Oct 2022

Topic Review

Adult Wistar Rats

Rats are considered adults from 2 to 5 months. During this period, they are used for experimentation in physiology and pharmacology. Adult rats, depending on their age, can be in a different physiological state, which can influence the results of experiments carried out on them. Despite this, age-related changes in adult rats have not yet been examined. Our results showed that as male and female rats progressed from 2 to 5 months of age there was a decrease in the level of motor and exploratory activities, and an increase in the level of anxiety-like behaviour. Age-related changes were dependent upon initial individual characteristics of behaviour. For example, animals that demonstrated high motor activity at 2 months become significantly less active by 5 months, and animals that showed a low level of anxiety at 2 months become more anxious by 5 months. Low-activity and high-anxiety rats did not show any significant age-related changes from 2 to 5 months of age.

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23 Aug 2021

Topic Review

The date seed is an important by-product for date fruit manufacturers. Its use as source of different added-value compounds could be of great interest. Oil accounts for around 5-13% of the seed weight and its composition in phytochemicals makes it valuable for the food, cosmetic, pharmaceutical, and chemical industries.

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13 Jan 2022

Topic Review

Vitamin B6 and Diabetes

Vitamin B6 is an essential nutrient for the human health. It is involved in more that 150 metabolic reactions which regulate the metabolism of glucose, lipids, amino acids, DNA, and neurotransmitters. In addition, vitamin B6 is an antioxidant molecule able to counteracting the formation of reactive oxygen species (ROS) and advanced glycation end-products (AGEs). Epidemiological and experimental studies indicated the reduced levels of vitamin B6 can cause diabetes. In contrast other studies show that diabetes decreases vitamin B6 levels. Thus these findings lead to envisage the existence of a vicious circle at the basis of the relationship between vitamin B6 and diabetes. This entry reports the main evidence concerning the role of vitamin B6 in diabetes and examine the underlying molecular and cellular mechanisms.

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28 Oct 2020

Biography

Sabrina Gonzalez Pasterski

Sabrina Gonzalez Pasterski (born June 3, 1993) is an American theoretical physicist from Chicago who studies high energy physics.[1] She describes herself as "a proud first-generation Cuban-American & Chicago Public Schools alumna."[2] She completed her undergraduate studies at the Massachusetts Institute of Technology (MIT), earned her PhD from Harvard University and is a rising PCTS Postdoctor

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12 Dec 2022

Topic Review

Chemical Composition and Quality of Saffron

Saffron is the commercial name for the dried red stigmas of the Crocus sativus L. flower. It is appreciated for adding color, flavor, and a particular aroma to different food dishes or drinks (paella in Spain, Milanese risotto in Italy, lussekatter buns in Sweden, and alcoholic beverages). It is considered a high-priced condiment (1500–2200 euro/kg) due to the considerable labor involved in its production since it requires manual harvesting as well as a laborious handling process (sorting, drying, and storage). Saffron’s principal producers are Iran and Spain, whereas the leading importers are Spain, Hong Kong, and the United States. Saffron’s quality is essential for consumers in the food industry and is based on the concentration of its apocarotenoids and their respective sensory attributes: crocin’s coloring strength, picrocrocin’s bitter taste, and safranal’s aromatic intensity

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14 Nov 2022

Topic Review

Prisoners of War in Islam

The rules and regulations concerning prisoners of war in Islam are covered in manuals of Islamic jurisprudence, based upon Islamic teachings, in both the Qur'an and hadith. The historical legal principles governing the treatment of prisoners of war, in shar'iah, Islamic law, (in the traditional madhabs schools of Islamic jurisprudence), was then a significant improvement over the pre-existing norms of society during Muhammad's time (see Early reforms under Islam). Men, women, and children may all be taken as prisoners of war under traditional interpretations of Islamic law. Generally, a prisoner of war could be, at the discretion of the military leader, freed, ransomed, exchanged for Muslim prisoners, or kept in bondage. In earlier times, the ransom sometimes took an educational dimension, where a literate prisoner of war could secure his or her freedom by teaching ten Muslims to read and write. Some Muslim scholars hold that a prisoner may not be ransomed for gold or silver, but may be exchanged for Muslim prisoners.

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23 Oct 2022

Topic Review

Fungal Metabolism

Fungi metabolism consists on a series of reactions that results in the biosynthesis of a huge number of compounds. These compounds area usually divided into primary and secondary metabolites. Primary metabolism is common to several species and usually produces compounds with the function of assuring fungi growth and development. Secondary metabolism refers to the production of compounds that are not indispensable during fungi development. Secondary metabolites are commonly referred as "natural products" and have been extensively utilized in the pharmaceutical, cosmetics and food industry. Fungal metabolism is an excellent source of compounds related to the improvement of human health, and a discussion on this application is presented below.

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18 Nov 2021

Topic Review

Cheilitis is a medical condition characterized by inflammation of the lips. The inflammation may include the perioral skin (the skin around the mouth), the vermilion border, or the labial mucosa. The skin and the vermilion border are more commonly involved, as the mucosa is less affected by inflammatory and allergic reactions. Cheilitis is a general term, and there are many recognized types and different causes. According to its onset and course, cheilitis can be either acute or chronic. Most cheilitis is caused by exogenous factors such as dryness (chapping) and acute sun exposure. Allergic tests may identify allergens that cause cheilitis.

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25 Nov 2022

Biography

E. Michael Jones

Eugene Michael Jones (born May 4, 1948) is an American writer, former professor, media commentator and the current editor of Culture Wars magazine (formerly Fidelity Magazine). Jones is known for his writings from a perspective which defends the Catholic Church in American society and overviews the decline of the Catholic communities which were assimilated into the secular American mainstream af

9.9K
29 Dec 2022

Topic Review

Supercapacitor Applications and Developments

The storage of enormous energies is a significant challenge for electrical generation. Researchers have studied energy storage methods and increased efficiency for many years. In recent years, researchers have been exploring new materials and techniques to store more significant amounts of energy more efficiently. In particular, renewable energy sources and electric vehicle technologies are triggering these scientific studies. Scientists and manufacturers recently proposed the supercapacitor (SC) as an alternating or hybrid storage device.

9.9K
28 Mar 2022

Topic Review

Water Footprint in Steel Industries

Steelmaking is a water-intensive process. The mean water intake against each ton of steel manufactured is ascertained as between 2 and 20 m3. Primarily, the stated requirement is in the form of make-up water to compensate for evaporation and mechanical losses and does not contribute to wastewater generation. Conversely, unit operations, such as rolling, continuous casting, pickling, etc., generate highly complex wastewater rich in polycyclic aromatic hydrocarbons (PAH), cyanide, ammonia, non-consumed acids, benzene, toluene, xylene, oil, grease, etc.

9.9K
15 Jun 2023

Topic Review

Extraction Methods for Anthocyanins

Anthocyanins are considered high added-value compounds due to their sensory qualities, colors, and nutritional properties; they are considered bioactive ingredients. They are found in high concentrations in many by-products across the food industry. At present, expensive raw materials and production technologies make the extraction of natural anthocyanins relatively expensive.

9.9K
18 Feb 2022

Topic Review

Ground-Penetrating Radar in Soil Studies

Information on the spatiotemporal variability of soil properties and states within the agricultural landscape is vital to identify management zones supporting precision agriculture (PA). Ground-penetrating radar (GPR) and electromagnetic induction (EMI) techniques have been applied to assess soil properties, states, processes, and their spatiotemporal variability.

9.9K
14 Jun 2023

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